Etymology
The French Bourbon dynasty is named for the lordship of Bourbon l'Archambault. The town's name derives from Gaulish Borvo, a local Celtic deity associated with hot springs, from Proto-Celtic *borvo (“froth, foam”), from Proto-Indo-European *bʰrewh₁- (“to be hot, boil”). Compare brew and fervent.
The subsidiary senses derive from the dynasty's name.